Porous medical implants are commonly infused with a variety of pharmaceutical substances including osteoinductive and nutritional factors, drugs, antimicrobial agents, calcium containing compounds, blood proteins and related materials; and growth factors to facilitate the implant's incorporation within the body and avoid unwanted complications resulting from surgery or the condition being treated. The infusion of substances into established materials such as collagen sponges is rapid upon contact with a solution or dispersion of the pharmaceutical substance. However, many of the newer load bearing materials, such as porous calcium phosphate ceramic, absorb pharmaceutical substances slowly and incompletely.
A number of techniques have been employed to eliminate gases from a porous implant and improve infusion of a variety of materials therein. U.S. Pat. No. 5,181,903 (Vann, et al.) issued on Jan. 26, 1993, discloses a method for eliminating undissolved gases and the incorporation of therapeutic agents into a biomaterial utilizing hydrostatic pressure. Prior to the application of pressure, the solution containing the therapeutic agent and optionally the biomaterials are degassed at reduced pressure, the biomaterial is submerged in the therapeutic agent and hydrostatic pressure is applied to all surfaces of the biomaterial.
U.S. Pat. No. 6,063,117 (Perry) issued on May 16, 2000, discloses a non-polyethylene orbital implant that can comprise a porous ceramic material and a method for infusing either gentamicin or a fibroblast growth factor prior to implantation. The implant was placed in a sterile 30 mL syringe, filled with enough solution to immerse the implant, the syringe capped and the plunger withdrawn to create a mild vacuum. Residual air was released upon slight agitation of the syringe barrel and by continued contact with the solution overnight at 4° C.
U.S. Pat. No. 5,769,897 (Harle) issued on Jun. 23, 1998, discloses a vacuum vessel that can be utilized for treating, storing and transporting an artificial bone material. The vessel disclosed is constructed of a rigid plastic, has an opening for insertion of the bone material, a lid to close and seal the opening and has two ports, one for connecting to a vacuum source and the other sealed with a self-sealing rubber membrane for the introduction of a pharmaceutical substance.
In spite of these advances, the need exists for an improved device for storing, transporting and infusing a porous implant and a method for the improved device's use.